Ringing burglar-alarm



(N0 Modal.) A. W. LAWSON.

RINGING BURGLAR ALARM.

N0. 2'77,296.- Patented May 8,1883.

WITNESSES IN ENTOR.

ATTORNEYS,

. UNITED STATES v PATENT FFICE.

RlNGlNG BURGLAR-ALARM.

SPECIFICATION forming part of Letters Patent No. 277,296, dated May8;"1883.

Application filed February 16, 1883. (No model.)

To all whom it may concern:

Be it known that I, ALLISON W. LAWSON, of Midway, in the county ofBullock and'State ofAlabama, have invented certain new and usefulImprovements in Door-Alarms; and 1 do hereby declare that the followingis a full,

clear, and exact description of the invention, which will enable othersskilled in the art to which it appertains to make and use the same,reference being bad to the accompanying drawings, which form a part ofthis specification, and in which- F igure l is a perspective view of apart of a door and door-frame provided with my improved alarm, with partof its inclosing-casing broken away; and Fig. 2 is at'rontview of thealarm.

Similar letters of reference indicate corresponding parts in both thefigures.

My invention has relation to that class of door-alarms adapted lobefastened to the frame of a door and to be operated by a projection uponthe edge of the door, which, when the door is opened or closed, willstrike a projection upon a bell-hammer, sounding a bell; and it consistsin the detailed construction and combination of parts of the same, ashereinafter more fully described and claimed.

In the accompanying drawings, the letter A indicates the casing orframe, in which the bell B and its operating-spring O are fastened, theback piece, 1), of the casing having both ends E projecting, for thepurpose of fastening it to the door-frame above the door. The bell B isfastened to the front piece, F, of the casing upon a lug or bolt, G,while the spring 0, upon the outer end of which is a hammer, H, isfastened in one end of the casing. This spring is fastened in the sideof a recess, I, in one of the end pieces, J of the frame, its inner bentend, K, being inserted into the side of the recess, whereupon it passesdown the side of the recess, and is clamped to the side of the recess bymeans of staples L. The spring is thereupon coiled, forming a spiral, M,and carried out to one side, forming a downward-projecting bail, N, andcurved upward and downward at its outer end, so as to project inside thebell, the hammer H being in close proximity to the lower portion of therim. A roller, 0, pivoted in a bracket, P,upon the upper edge of thedoor, engages bail Nwhen the door is opened or closed, pushing it andthespring upward, causing the hammer to strike the bell as thespringrebounds.

It will thus be seen that the door cannot be opened or closed withoutgiving alarm, and that by the simplicity of construction of the springthe alarm does not easily get out of order.

By making slight changes in the arrangement of the roller and spring thealarm may be applied at any place or objcctsuch as sh utters, drawers,trunks, &.c.--without changing the spirit of my invention.

Having thus described my invention, I claim and desire to secure byLetters Patent of the United States- In a door-alarm, the combination ofspring 0, fastened in a recess, I, in the end piece of theinclosing-casing A by its bent end K and spiral M and bail N, and havinghammer H, with the bellB,fastened to thefront piece of the frame A, androller 0, pivoted in bracket P upon the upper edge of the door, as andfor the purpose shown and set forth.

In testimony that I claim the foregoing as my own I have hereuntoaffixed my signature in presence of two witnesses.

. ALLISON W. LAWSON. Witnesses:

l W. J. JORDAN,

(LIMIGKINNON.

